Four of us, jammed into my sister's Ford Festiva, going to kill the monster. Sylvia drives. The Hum has left her untouched, so she's the only one left in town who can drive. My sister licks the palm of her hand, touches it to her nose and bumps her forehead against the steering wheel. Then she does it again.

"Today would be nice, sis." I say. I'm in the back seat with June, a twelve-year old girl clutching a teddy bear to her chest.

"All right. I'm ready." Sylvia twists the key, and the car starts. We back out of the driveway.

"The streets are so empty," she says.

"That's because everyone is dead," Michael tells her. "They listened to the Hum and went into their houses and pulled the covers over their heads and died. I had a hamster that died, once. It got real old, so it made a little nest, and then it laid down in it and died."

"We're not dead," I say.

"Not yet," Michael corrects me. "Give it time."

It started a week ago. Tuesday morning, hot day, storm clouds gathering like bad thoughts. I walked out to my car. I was going to work, the way normal people do. I'm not normal, but I've gotten good at pretending.

I saw a robin fluttering its wings on the sidewalk. At first I thought its back was broken, but when I came closer it squawked and ran onto the lawn. It gave a little hop, flapping its wings, and then hopped again.

I put my hands to my temples. My head hurt. I hadn't slept well the night before, and I could feel the beginnings of a migraine forming. I looked at the robin, hopping and flapping its wings on my lawn. It didn't look injured; it looked like it had forgotten how to fly.

I shrugged and walked away. The bird's behavior was strange, but I needed to get to work. So I went. When I drove home that evening the sidewalks and streets were covered with birds, all squawking and flapping their wings.

The bird story made the nightly news. The newswoman stood in Buehler Park surrounded by a flock of distressed pigeons. She talked too loud and stumbled over her words. Her voice sounded a bit slurred, like she was drunk.

"Put something else on," my wife said. We were eating dinner in front of the TV, the way we did when things were good between us.

"All right." I shrugged and switched the channel. We watched a movie, and I forgot all about the birds.

The next morning my wife went blind.

We pull into Shop-Rite's parking lot. Normally it's jam-packed. They average three fender-benders a week, because the designers of the lot made the lanes too small, the spaces too tight. But today we drive right in.

"This is far enough," Sylvia says, and stops the car next to an overturned garbage can. "You can walk the rest of the way."

"You can go a bit closer, I think." I turn to Michael, our expert. "How close can we get?"

"The spygers' kill zone is ten parking spaces out," he says, pointing. "You can see they cleared the area of shopping carts and everything."

But Sylvia is shaking her head. "If you want to commit suicide, Jimmy, I can't stop you. But I'm not going to have you kill the rest of us."

"Here they come," Michael says.

The spygers gallop out of the supermarket. They're the size of ponies, with insectile bodies: head, thorax, abdomen. They skitter towards us on six legs. Their heads are blunt like hammers, their bodies covered with a fine brown fur dappled with black stripes.

The spygers stop about twenty feet away and form a semi-circle. I look at Sylvia, face pale, breathing harsh, hands never leaving the steering wheel. Her knuckles are white.

"Sing, sing." June shouts, hugging the teddy bear to her chest.

"See, I told you." Michael says. From the tone of his voice you'd think we were discussing the weather. "I watched the spygers last Tuesday. I got hungry, so I went to the supermarket because that's where you get food. I didn't get anything to eat, but I saw how the spygers work. One of them stands guard, the rest stay in the supermarket. When somebody comes they all run out, but they won't cross the line. As long as you don't cross the line, it's safe."

"What are they doing?" Sylvia asks.

"They're guarding it," I tell her. "Whatever's making the Hum."

"It's symbiosis," Michael says. "A relationship between two different species. Ants harvest aphids for the honey. Wasps use moth eggs to hatch their young. I saw it on a Discovery Channel special."

"Those things might be bugs but they don't look like they eat honey," I say.

"The spygers aren't bugs," he tells me.

"They look like bugs to me."

"Arthropods can't grow that big. They don't have skeletons."

"Let's not argue," Sylvia says.

"Sorry." That's me, arguing with a kid.

It wouldn't be so bad, except I'm losing.

"James. James." I heard my wife calling my name. "Wake up, James."

"What's wrong?" I opened my eyes and saw sunlight streaming through the curtains. I peeled away the covers and sat up. The left side of my body felt numb. My fingers tingled, and my teeth hurt. I heard a low monotonous drone in the background, like a dial tone.

"Jesus." I waved my hand in front of her face and she didn't react. "Hold on." I limped to the living room and searched my desk drawers for a pocket flashlight.

"James, where are you?" Her voice rose. "Don't leave me."

"I'm coming." When I stumbled back into our bedroom my wife's face was slick with tears. I put an arm around her waist and pulled her closer. My chest tightened, my throat closed up, I felt like running; and then the panic attack passed, the way it always did. My wife pressed the side of her head against my shoulder, and for a moment I thought that it was going to be all right.

"Hold on." When I shone the pocket flashlight into her eyes the pupils constricted. "Your eyes are responding to the light," I told her.

The spasms hit in the living room. I fell to the floor. I couldn't move. I heard my wife's screams, louder and louder, turning to sobs; I heard her stumbling about, colliding with walls; and then the sounds faded, and all I heard was the Hum.

The spygers crouch in a semi-circle, facing the car.

"What are we going to do now, Mr. Bruschi?" Michael asks.

"You don't know?" I say. "I thought you knew everything."

June puts her hand over her mouth and giggles. So someone else finds Michael annoying.

Sylvia twists in the seat and glares at me.

"I'm sorry, Michael." I say. "That was mean."

"That's all right," he tells me. But his eyes are too bright, and his lower lip quivers. I wish we didn't have to bring Michael and June, but they get hysterical if we leave them alone. I guess I'd feel the same way if I was a kid.

"Just get on with it, James." Sylvia says. She only calls me James when she's pissed.

"All right." I press the button and the window rolls down. The spygers don't move, don't rush forward to drag me out of the window and gobble me up. A cool autumn breeze blows in, crisp and clean, but I smell something else, a cross between rotten bananas and road kill.

"Smell that?" Michael asks. "I bet it's using pheromones to control the spygers."

"Could be," I say. Or it could be all the decaying produce in the supermarket, but I don't want another argument.

I reach into the cooler sitting at my feet. Feel raw, wet meat against my fingers. The hamburger is rolled into neat spheres the size of baseballs. I toss one out the window and it drops to the ground at the lead spyger's feet. Plop.

"What are you doing?" Michael asks.

"Wait and see," I say, leaning back on the seat. The spyger pokes the meat with a claw. It lifts a chunk to its hammerhead and sniffs, a loud snuffling sound. Then it gobbles it down. The others watch, keeping a respectable distance as the spyger shovels the rest of the hamburger down its maw.

It doesn't take long. The spyger begins to sway, reeling about like a drunk. It collides with an upturned shopping cart and collapses in a heap, its legs twitching, its body convulsing, vomiting foul-smelling chunks onto the pavement.

"You poisoned it," Michael says. His eyes are huge. "You put poison in its meat and it ate it and it's going to die."

June laughs, a loud horsey sound. Her eyes are shining.

"I want my muh-mother," Michael says, and starts to bawl. Sylvia puts her arm around his shoulder. I know it's hard for her, because she doesn't like being touched. Neither of us do. I don't remember Mom touching either one of us. Touching wasn't a Mom thing.

Michael throws his arms around Sylvia's neck and jams his head against her shoulder and really lets loose. Sylvia makes a face, but she doesn't let him go, and I think about Michael's mother, a nice woman who always smiled, always said hello. Michael won't say what happened to her.

"Get on with it," Sylvia whispers. "I don't want him to see this."

"All right," I say, but June is ahead of me. She wrenches open the cooler cover and flings chunks of raw hamburger meat out the window. The spygers fall on them, greedy.

"Beans! Blowtorches!" June shrieks. "Bologna sandwiches!"

Her teddy bear lies on the seat, forgotten.

I woke to the feeling of someone pinching my nose. My mouth opened. A series of grunts came out. Lying on the floor, my ears ringing, I felt my body constricting, drawing into itself.

When I opened my eyes I saw my sister bent over me. She wore her Wednesday outfit, stonewashed jeans and a lime-green blouse. I saw her bra strap, a lighter shade of green, poking against her shoulder. She'd been wearing the same Wednesday clothes, bra included, for years.

"Listen to me, Jimmy. You need to fight it. Fight, okay?"

I moaned. My body was paralyzed. I could move my head back and forth, and that was about it.

"Remember when we were kids?" she went on. "Remember when you counted cracks? Do that again. Count cracks. It's the only way."

So I looked at the floor and I counted cracks. I started by counting tiles. My living room had four hundred and eighty tiles, a nice even number. Each tile-side counted as a crack, which meant one tile equaled four cracks, a row of twenty-four tiles equaled ninety-six cracks, and twenty rows of twenty-four tiles equaled 1,920 cracks. 1,920 cracks counted twenty-four times equaled 46,080 cracks.

I counted cracks for hours, my mind falling back on the old patterns, calculating, and by the end of the day I could move my right arm.

Sylvia stayed with me. She fed me, she cleaned me, she talked to me, just like she had done for Mom.

After three days I could move. My left side didn't work too well anymore, but if I took it slow I could manage.

I was alive.

But my wife was dead, along with the rest of the town.

"I'm going in," I say. It's been five minutes since the last sypger keeled over.

"Don't wait too long." I struggle with the door handle, my fingers clumsy. June reaches over and opens it for me. "Thanks."

"Snausages," she says.

"We'll wait for you." Sylvia repeats the words.

My left leg is bad today, so it takes forever to get out of the car. Sylvia doesn't help. She stares straight ahead, face set, arms folded to her chest. When I finally make it out I lean against the Festiva's side, panting and sweating. June hands me the shotgun, which I tuck under my right arm. And then she gives me my cane.

"Let's just get out of here," Sylvia says. "We can drive away. Get help."

"If you have to go, go." I say. "We spent hours arguing about this last night, sis. I'm all argued out."

"There might be more spygers in the supermarket," she says.

"If that's true, I'm dead." When I try to grasp the cane in my left hand it clatters to the ground.

"Do you have to go, Jimmy? Do you have to do it?"

"I'm going to kill it, Sylvia. Whatever it is."

"You always did have a nasty streak," she says.

I shrug. Kneel, very slowly, and retrieve my cane.

"I love you," she tells me.

I start the long walk to the supermarket. And then I hear the car door open, and June runs up. She slides her arm under mine, propping me up.

"June, go back." I tell her. "It's not safe."

"Toasters," she says.

"Go back to the car," I say, but June shakes her head. If she wants to follow me, I'm in no shape to stop her. There's nothing I can do. Well, I could turn around and head for the car. She wouldn't go in to the market by herself. But I'm not turning back.

Better that we stick together, then.

"Stay with me," I say. "Don't leave my side."

June nods.

"Why would you want to come with me?" I ask, giving it one last try. "We'll probably die in there."

June grins, a slow hot grin that shows lots of teeth. She rears back and kicks a spyger in the head.

"Don't do that," I tell her, looking down at the spyger's body. The top of its hammerhead is smooth and unmarred.

"They don't have eyes," I say.

June shrugs, a so-what? gesture.

"They're blind," I tell her. "So we've got to be quiet. You understand? Be quiet. In case there's any more in the supermarket."

"Baby shampoo," June says. She nods, just to let me know she gets it.

The entrance to the Shop-Rite is open, the electronic doors torn from their hinges. We walk in. Shattered glass crunches under our feet. The lights are still on. Someone must have turned on the back-up generator. Canned goods litter the ground, and the stench of rotting vegetables fills the air.

June gasps. Then she puts her hand over her mouth.

I look down the aisle.

See the spyger, bigger than a horse, galloping towards us.

I looked down at my wife, lying on the bed. She wore her baby blue bathrobe, the one I'd given her for her birthday. A slipper hung from her right foot. She'd knocked the comforter to the floor. She was curled up into a ball, hands over her ears, mouth stretched open in a silent scream.

"That's all right," I said, because I couldn't think of anything else to say. I cleared my throat. "How are your cats doing?" Sylvia had three of them, all large and well-fed.

"Socks died this morning. He stopped eating." Sylvia said, her eyes filling up. "Pumpkin curled up into a ball and died. Munchkin started grooming herself and wouldn't stop. She bit chunks out of herself until she bled to death."

"I'm sorry, sis." I put a hand on her shoulder and watched her cry.

I envied her, being able to cry. My wife was dead, and I couldn't cry. The grief was locked down so deep I couldn't even feel it. I wish I could say it was because of the Hum, that the Hum had shut me down emotionally as well as physically. But it wasn't the Hum.

That part was all me.

And that's when I knew I was going to kill the Hum, whatever it was.

"Sorry." Sylvia wiped her eyes. "Every time I think I'm all cried out, it starts up again."

"Did the Hum kill everyone in town?" I asked.

"Not everyone. There's Michael Johnson. He's nine years old. He comes into the library with his mother and takes out fifty books at a time." She grimaces. "Or he used to."

"And that's it?"

"No. There's also June Dorringer. She's twelve years old. Her family lives down the block from me. I heard June crying, so I went in. Her family is dead, but June is all right. Except the Hum impaired her."

"What do you mean?"

"She can't talk. She can think all right, but the words that come out are gibberish. Michael and I seem to be the only people who are immune. I guess the voices in our heads are louder than the Hum." She laughed, a bit too loud. "Anyway, they're downstairs in your den, watching old episodes of Cheers. I brought my DVDs with me."

I picked up the comforter and threw it over my wife's body. Smoothed it over. "What about the rest of the world?"

"I have no idea," Sylvia said. "I haven't seen a car or a plane in days. The TV and radio don't work. So I don't know if it's just here, or if the rest of the world's been affected."

"What do you think happened?" I ask. "Was it a military experiment? An alien invasion? Some kind of nerve gas?"

"Who knows?" Sylvia said, shrugging. "Does it really matter?"

"Of course it matters."

"Things don't always make sense. There isn't always a reason." She sighed. "There may be other people alive in town. But they're in their houses, hiding."

"Why would they hide?"

"Because they're scared," Sylvia said. "Scared, and ashamed."

And her voice cracked a little bit.

I toss the shotgun over the spyger's head. It hits the ground with a clatter. The spyger slides to a halt at the top of the aisle, confused, swiveling its head back and forth. June and I stand, frozen, less than two feet away. If I reached out I could touch it.

We should be dead. The spyger can't see us, but it has other senses. Smell, probably, and it can hear just fine. I look at June. Her eyes are huge, like saucers. Tears trickle down her cheeks. But she keeps both hands over her mouth and doesn't make a sound.

The spyger sneezes, a loud explosive belch. It wheels suddenly, colliding with a shelf, and I realize why we aren't dead. The spyger is sick. It reeks of road-kill and rotten bananas. Drool spills from its open mouth.

The Hum is killing it, also.

My fingers curl around a can of Chunky Tomato Soup. I throw the can as hard as I can, and it hits the far wall, and the spyger gallops after it, hissing like an enraged steam kettle. Its head hits the wall with a crack. It bounces back and tumbles to the floor.

I almost laugh. Instead I wait until the spyger has regained its feet, and then I throw another can. The spyger chases it straight into the aisle divider. Cans of baked beans tumble onto its head. It rises, shaky.

June and I throw cans at the walls for almost a half-hour. We watch as the spyger kills itself, slowly, in the grips of a compulsion it can't control. Leaping, colliding, falling, getting up, again and again and again.

I counted cracks when I was a kid. My sister touched things. We were a pair, the two of us. My mother used to say we'd fallen out of our cribs as babies. It was a joke, I guess, but I was just a kid and I didn't know that, so one day I asked her how come she'd let us fall out of our cribs.

I still remember the look on her face.

Autumn was a bad time for both of us. Sylvia tried to touch each and every leaf on the way to school. I pushed them back and forth with my feet, and tried to count them. Leaves weren't cracks, but they covered the cracks, and so they counted as cracks, and I counted them. That was my reasoning, anyway.

And then it stopped. I woke one morning in October, and the urge to count cracks was gone. It was like an alarm clock went off in my head. I was cured. That's what I thought, anyway, at the time. But Sylvia was as bad as ever. When we walked to school together she still touched things, iron railings, mailboxes, trees.

One day I got tired of waiting. Sylvia was licking the palm of her hand and touching a telephone pole and I just kept walking. Sylvia watched me go. I saw her face, the way it sort of crumpled. But she didn't call out, or tell me to stop.

I wouldn't have stopped, anyway.

"I'll get the—" I say, and then the Hum gets louder, like someone's turned a radio dial and kicked up the volume.

June screams and presses her hands against her head. I topple to the floor. My left side is dead, my ears are ringing, my body is constricting. But the floor of the Shop-Rite is scuffed, and scuffs count as cracks. I count twenty-seven cracks seven times, and then I feel pins and needles in my leg, and I can get up. Barely. If I fall again I don't think I'll be getting up.

I see June, hands over her head, curled up into a little ball like a dead bug. I feel a burning in the pit of my belly. She's twelve years old, and I've killed her. She's dead. I'm sure she's dead, she has to be dead, because I can't deal with her right now, my strength is fading, and I need to kill the monster.

I have to walk away. The way I walked away from my wife. The way I walked away from my sister, years ago. The way I walked away from every single goddamn thing in my life I couldn't deal with.

Something in my chest gives. I limp over to June. Shake her shoulder. When she doesn't respond I pinch her arm, hard. She uncurls. Her eyes fix on mine. She opens her mouth, but all that comes out is a harsh croak.

"June. Get up," I say. "Come on. You can do it."

I hold out my hand. She takes it. After the third try she makes it to her feet.

"It's all right," I tell her. "It's going to be okay. When we kill it everything will be all right. Things will go back to normal. You'll be able to talk again."

June points at her throat. Makes a croaking sound.

"I know. I'm sorry. I count cracks, and that makes it better for me. I don't know what you do, if you count or touch things or whatever. If you have a ritual, use it. It's the only thing that can fight the Hum."

June's eyes widen. In recognition? I don't know. I've never been very good with people, at reading them, their wants and fears. She hugs me, and then she's off, running down the aisle.

I turn to the spyger, lying on its back, its legs twitching. It has a backbone. I know because I heard it snap after its last collision with the wall.

June runs up holding the shotgun in her arms.

"I soaped the herring," she says, handing it to me. "You snowshoed it."

"Thanks," I say, taking it from her.

"Prime numbers. I glork them. Up here." She taps her head. "Didn't know. Would have bicycled it sooner."

"I'm sorry, June. I should have told you."

"That's spaghetti," she says, touching my arm.

We walk towards the spyger. It hears us coming. It tries to rise, but it can't.

It doesn't want to fight. Not anymore. It's trying to run away.

"Turn away," I tell June.

"No," she says, shaking her head. "I want to see."

I jam the shotgun into the spyger's mouth. Its jaws snap shut and it gnaws at the shotgun, feeble, like a baby sucking its mother's tit.

They fucked up.

They're stronger than us.

They're faster than us.

Doesn't matter.

They're bugs. I don't care what Michael says. They're bugs. And we've been squashing bugs for ten thousand years.

I pull the trigger.

My sister graduated high school. She never went to college, even though her grades were good enough. Instead she got a job at the local library shelving books. She would walk down the aisles, lightly touching the books, rearranging the ones that were misshelved. It was a job she liked, I guess. I never asked her because I was too busy going through the motions, college, job, marriage, getting older.

Sylvia moved into her own place, a little one-bedroom apartment above a laundromat that she shared with three cats. She went to the movies every Friday, no matter what was playing. She wore the same clothes, according to the day of the week. People talked about her, they called her the Licking Lady, but she didn't seem to care.

She even seemed happy.

I hope she was happy.

And then Mom had her stroke, and Sylvia moved back into our old house and spent five years taking care of her, and that's when I re-entered my sister's life. I started visiting. I bought groceries. I helped her clean. I ate over three times a week, always the same food, and on nights when things were bad with my wife, I slept in my old room.

She slides her arm under my shoulder, propping me up. We walk to the back of the store, where the Hum is stronger. We pass containers of purple meat, putrefying fish rotting on bare white slabs, the ice cubes melted away. I don't see any bugs; the Hum must have killed them, too.

The back room is brightly lit and full of sharp objects, rows of glittering knives, gleaming machines, slicers and dicers. I see the meat locker, the door closed and bolted. That's where it lives. Must be. So it needs cold air.

The Hum rises a notch. My left eye droops shut like a drawn curtain. My left fingers curve into a claw. I fumble at the lock with my right hand. June pushes my hand away and unlatches the door. It swings open.

I hear her scream.

The grayish lump covers the far wall, like a wasp's nest or a tumor. It has eyes, a pair of them, huge eyes, no lashes, opening and closing, blinking lazily.

Kitten eyes.

The Hum becomes a scream in my head.

"Sylvia." It was my mother speaking. She sat on her favorite chair, a quilt curled around her knees, a purring cat on her lap. We'd just finished eating dinner, pot roast with green beans and mashed potatoes. Which meant it was Thursday.

"What is it, Mom?" My sister was watching an old episode of Cheers.

"I know I haven't been a perfect mother," she said, clearing her throat. "I know it. But I love you. I just wanted you to know."

"There are treatments. For your problem." Mom tapped her head. "You can get treatment."

Sylvia froze. Her left cheek twitched, and then smoothed over.

"Good idea," she said. "I'll get treatment. And while I'm at it I'll pay for someone to watch you so I can go to college. My job at the library will pay for it, right? And then I'll fall in love and have kids. After all, I'm only thirty-nine years old. I've got my whole life ahead of me, right?"

"Sylvia—"

"Don't do this to me, Mom." Sylvia said. "If you do love me. Don't."

Mom nodded. Ten minutes later she was asleep, her mouth wide open, snoring.

Sylvia went to bed early. I didn't sleep over. I went home and slept on the couch.

And that was the last time anyone in our family ever said anything.

I topple to the floor. Something tears at my head, its breath wet and hungry.

And then I hear June.

"2, 3, 5, 7, 11, 13," she shrieks, leaping over me. I see a butcher knife in her right hand. "17, 19, 23, 29, 31."

She plunges the knife into the kitten eyes, over and over.

The Hum wavers, and then dies.

I struggle to my feet. June is chopping the gray lump into pieces, spitting out numbers. When the butcher knife falls out of her hands she starts beating at it with her fists.

"June, stop it. Stop it."

My voice is hoarse. I hold out my arms. June turns away from the gray lump and runs to me. She puts her arms around my waist and squeezes so hard it feels like my spine is about to break. I hug her back. The top of her head pokes against my chin, and I can smell her shampoo, the Johnson's Baby Shampoo she's washed her hair with.

I look over her head, at the gray lump, already starting to disintegrate.

It's dead.

The Hum is gone.

Yesterday Michael saw an airplane, trailing white spume, streaking across the sky like an angry hornet. We all agree it's a sign.

There are twenty-seven of us now. I spent the last week walking up and down the streets, looking for survivors. And I found survivors, twenty-three children, half-starved, huddled in closets and basements, hiding. The Hum killed the rest of the adults. Once you get past a certain age, you set. You aren't flexible enough.

Today is the day.

We're going.

We'll load everyone onto the school bus.

Sylvia will drive. My left side still doesn't work too well, and I don't think it ever will.

Strange Horizons is a weekly magazine of and about speculative fiction. We publish fiction, poetry, reviews, essays, interviews, and art. For more information, see our about page. All material in Strange Horizons is copyrighted to the original authors and may not be reproduced without permission.